Interlocking electric plug



P 19, 1939- J. R. DINKINS INTERLOCKING ELECTRIC PLUG Filed April 14,1958 In ventor Ji 1721227205325;

A flforrieys Patented Sept. 19, 1939.

v UNITED STATES N PATENT f orrlcs mp PLUG I I x Joseph 1:. mnkim.Amwalt, w. Va. Application April 14, 1938, semi No. "2,081

1 Claim. (!;173-343);

This invention mates to an interlocking plug,

the general object 01 the invention being to provide means forlockingthe prong carrying part of the plug to-the socket part by apartial tuming movement of one part relatively tothe other,

with means for insuring an eflicient' electrical connection between theprongs and the contact members in the socket part.

This invention also consists in' certain other features of constructionand in the combination and arrangement of several parts, to behereinafter fully described, illustrated in the accompanying drawing andspecifically pointed out in the appended claim.

I' iescribing the invention in detail, reference will be had to theaccompanying drawing wherein like characters denote like orcorresponding parts throughout the several views, and in which:

Figure 1 is an elevation with parts in section or the complete device.

Figure 2 is a section on the line 2 2 or Figure 1 looking in thedirectionindicated by the arrows.

Figure 3 is a fragmentary sectional view taken at right angles to Figure1.

Figure 4 is a view looking into the inner end of the prong carryingpart.

In these views the numeral I indicates the socket part oi the plug whichis provided with the usual threaded portion 2 andthe numeral 3 indicatesthe prong carrying part, the prongs of which are shown at 4 and eachprong has a ball 5 at its free end. The prong receiving end of the partI is formed with a pair ofarcuate slots 6' each of which terminates atone end in a circular hole I, the hole being large enough tor thepassage of the ball 5. Within the socket are the pair of spring contactmembers 8 each of which has its ireeend formed with a pair of springarcuate-shaped jaws 9 for receiving the prongs 4 below the heads orballs 5, and these jaws are aligned with the slots 6 so that when theprongs as; passed through the holes I and then the part 3 given apartial turning movement the prongs will enter the jaws and be grippedthereby below the balls. One of the members -8 has an extension 8' whichengages the metal part {and the other member 8 is connected with themetal strip 8" which connects with the center contact 2' which, ofcourse, is insulated from the part 2.

Thus it will be seen that when the prongs are placed through theopenings I and one of the theiaws and the two members members slightlyturned the prongs will engage and I will be connected together in such amanner that they cannot be pulled apart without turning one member in areverse direction to place the balls I 5 in registry with the openings 1and when this is done the prongs will move out of engagement withtheiaws. Aswilialsobeseenthebalisi also act to prevent the prongs beingpulled from the jaws until one member is turned relative to the m otherto place the prongs in registry with the holes].

It is thought from the foregoing description that the advantages andnovel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction andin the combination and arrangement of the several parts, provided thatsuch cha'nges tall within the scope ofthe appended claim. 1

Having described the invention, what is claimed as new is:

said larger ends and the plug rotated to enter said shanks in thereduced parts of said slots, a pair of arms extending from said webinwardly of the socket member from adjacent the reduced ends or saidslots, respectively, and secured to 40 said web, said arms terminatingin a pair of resilient -jaw members, respectively, curved concentricallyto said slots and spaced apart in coni'ormity therewith, said pairs oflaws opening towards the larger ends of the slots to receive 45 theshanks of said prongs therein under rotation of the plug member to enterthe shanks in thereduced parts of the slots, and said pairs of laws andterminals coasting under such rotation of the plug member to cam saidmembers together.

JOSEPH R. DINKINS.

